Page 33 - EngineerIT July 2022

TECHNOLOGY

Radio waves to protect computers

p to now, protecting hardware
against manipulation has been
Ua laborious business: expensive,
and only possible on a small scale. And
yet, two simple antennas might do the
trick.
Radio waves could protect
computers, as well as card readers, from
attacks on their hardware. As a team
from the Max Planck Institute for Security
and Privacy and the Ruhr University
in Bochum has shown, the signal from
one antenna in a device generates a
characteristic electromagnetic pattern
that is received by a second antenna. If
an attacker manipulates the device with a
wire, for example, the radio wave pattern
changes and blows the whistle on the The researchers can monitor an entire system, such as a server, with simple radio antennas (pink)
manipulation like an alarm system.
Payment transactions, business components via conductive paths. A laid the foundations for this technology
secrets, documents that are important tiny metallic object, positioned in the when he was a RUB researcher.
for national security: today, the world’s right place on the hardware, can be
most valuable secrets are often no longer enough to tap into these data streams. Protection through radio waves
stored on paper, but rather as ones and “Fraudsters have used this simple Mechanisms designed to protect
zeros in virtual space. When we suspect method, for example, to tap credit card hardware from tampering do exist,
that these secrets are in danger, we data from card readers,” say Paul Staat of course. “Typically, it’s a type of foil
usually imagine a threat from afar – and Johannes Tobisch. Both are doing with thin wires in which the hardware
attackers trying to capture confidential their PhDs at Ruhr-Universität Bochum component is wrapped,” explains
data through cyberattacks. But there (RUB) and conduct research at the Max Staat. “If the foil is damaged, an alarm
is another threat, a much more direct Planck Institute for Security and Privacy. is triggered.” However, this method
way to get into other people’s systems, As members of Christof Paar’s team, can only be used to protect small
namely by tampering with the hardware. they are developing methods to protect components, not the whole system: it’s
The valuable information is ultimately against hardware manipulation. They are impossible to wrap an entire computer
nothing more than electrical currents cooperating with Christian Zenger from case in the foil, typically only an
that travel between different computer the RUB spin-off company PHYSEC, who individual key component like a memory
element or a processor, for example.
Tobisch and Staat are working on a
technology that would monitor entire
systems for manipulation – and wouldn’t
be so expensive.
For this purpose, the researchers
employ radio waves. They install two
antennas in the system that they want
to monitor: a transmitter and a receiver.
The transmitter sends out a special
radio signal that spreads everywhere in
the system and is reflected by the walls
and computer components. All these
reflections cause a signal to reach the
Paul Staat ( left) and Johannes Tobisch are doing their PhDs at RUB and conducting research at receiver that is as characteristic of the
the Max Planck (© Michael Schwettmann) system as a fingerprint.

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